The present invention relates to a lid member for food container, more particularly, to an improvement of a lid member to be used for containers for quickly cookable foods.
Conventionally, quickly cookable foods like chow mein, spaghetti, polished rice and sekihan (steamed rice with red beans) or the like have been distributed as a sort of quickly cookable foods to be cooked by pouring thereinto hot water, leaving it for a predetermined time and removing therefrom the hot water.
As the containers for quickly cookable foods to be cooked by removing such poured hot water, their popular structure have a cup-shaped container body and plastic lid member mounted thereon. Container bodies for such containers were usually produced by thermoforming expanded resin particles (expandable resin beads) made of polystyrene resins and a blowing agent like butane, pentane or the like. Then, the popular plastic lid members are sheet-formed and have discharge apertures at their outer circumference. These plastic lid members are simply to cover the container body, more particularly, the lid member is engaged with the container body through their projections by engaging such projections with grooves provided on the flange at the outer circumference of the lid member.
With reference to FIG. 7, the conventional plastic lid member 100 has a pair of apertures in mutually opposite positions at the lid circumferential edge. These apertures are to discharge the poured hot water from the container body and have slit blade a. When the blade a is stood up, apertures to discharge the hot water from the container are formed.
However, numbers of such apertures to be formed at a restricted area in the flange are limited, therefore, the discharge rate of the hot water is accordingly limited, thus, it usually takes a longer time to remove the hot water. Then, when apertures are blocked by the foods in the container, a still longer time will also be necessary to remove the hot water. Further, when the blade a is broken, their fragments might enter the container. Further, sealability of the container is not good, thereby, moisture might penetrate into the container through the space formed by standing up blade a and space formed between the lid and the container covered thereby.
In addition thereto, since most of such conventional lid members 100 were sheet-formed products, when the container body is covered therewith, the size of the container became unfavorable due to their bulk, and further space was necessary in transportation or storage thereof.
Further, in consideration of the consumers"" interest expressed and increased recently on an environmental issue, it is not preferable to dump these plastic lid members.
Then, when such containers were not handled well during the discarding of the hot water, the lid member is disconnected from the container body, and food stuff together with hot water will then be spilled therefrom. Accordingly, there is a potential danger of suffering from burning, and it is necessary to securely hold both of the container and the lid member during such discharging step.
Incidentally, Japanese Utility Model Publication No. 61-3810 (Prior Art) discloses a container for quickly cookable foods utilizing a lid member made of paper. This utilizes paper as a base layer and is to stick to the opening of the container.
With reference to FIG. 8, lid member 200 has substantially the same circumference size with that of the opening in the container body, then the discharge apertures 204 appear on the surface of the lid by pulling up the tab 203 integrally formed on the member 200.
The lid member 200 is formed by laminating polyethylene, aluminum foil or the like onto the base paper. In the container wherein the lid member 200 is stuck to the container body, the discharge apertures 204 are formed by pulling up the tab 203 integrally formed on the lid member 200, then, the easily-peelable area D is separated from the slit linking both foot-ends b, b around the tab 203.
The lid member 200 according to the prior art is more suitable to seal the container than the conventional lid member 100 (FIG. 7), and it reduces the bulk of the container; thereby, they are easily manufactured and dumped. According to this structure, however, the tab 203 may be broken at the slit linking both ends b, b when the tab 203 is pulled.
Then, the tab 203, positioned opposite to the tab 202, is placed around the center in the circumferential edge of the easily-peelable area D, therefore, it is necessary to pull up the tab 203 to open the apertures, such that the pulling force should be applied radially and equally toward the tab 203 as a center. Accordingly, considerable force and knack were necessary to separate the easily-peelable area D, thereby, the tab 203 itself may be broken at such peeling step.
In view of such inconveniences in the prior art, the present invention is to provide a lid member for a container of quickly cookable foods which can discharge hot water, in particular, it has excellent sealability with a container body, it allows the discharge of hot water safely and rapidly, its discharging apertures are easily formed, and it can be easily disposed of as waste.
With reference to FIGS. 1 and 2, a lid member for food container (hereinafter simply referred to as xe2x80x9clid memberxe2x80x9d) according to the present invention which can discharge hot water is a lid member 1 wherein it has substantially the same circumference as that of an opening 15 and will be stuck to the opening 15 of a container body 14, and it has a layered structure in which a base layer 20 and a surface sheet 40 are laminated through an adhesive layer 30.
The lid member 1 has an easily-peelable area A of the layered structure, having lubricant 11 additionally between the base layer 20 and the surface sheet 40; a non-peelable opening area C of the aforenoted layered structure placed within the easily-peelable area A; a non-peelable area B of the aforenoted layered structure placed adjacent to the easily-peelable area A; and the lid member further has:
a first tab 2 to peel off the lid member 1 from the container body 14, and
a second tab 3 formed at the side on the easily-peelable area A along the boundary line between the non-peelable area B and the easily-peelable area A to open the discharge apertures of the opening area C by peeling off from the lid member 1 a surface sheet in the easily-peelable area A.
Then, the lid member 1 comprises a series of slits 4-6, wherein:
a first slit 4 which is cut from the base layer 20 to the adhesive layer 30 and forms discharge apertures in the opening area C,
a second slit 5, which is cut from the surface sheet 40 to the adhesive layer 30, along the boundary line between the easily-peelable area A and non-peelable area B, and
a third slit 6, which is cut from the base layer 20 to the adhesive layer 30 and is placed where the second tab 3 is mounted, from the foot-end d of the second tab 3 spaced from the second slit 5 to the cross position e with the second slit 5.
According to the lid member of the present invention, the surface sheet in the easily-peelable area A can be easily and securely peeled along with the second slit 5 by pulling up the second tab 3, thereby, a desired number of discharge aperture(s) can be formed.
According to the other embodiment of the present invention, with reference to the FIG. 1(B), a lid member is arranged so that at least a part of the third slit 6 in the lid member 1 is placed on the sticking portion 17 substantially corresponding to the circumferential edge of the opening 15. In this case, preferably, the cross position e by the second slit 5 and the third slit 6 is placed on the sticking portion 17.
By thus arranging the third slit 6, since the surface sheet 40 can be peeled smoothly from the base layer 20 along the third slit 6 while the second tab 3 can also be peeled completely, the second tab 3 can easily be pulled.
According to the another embodiment of the present invention, with reference to FIG. 4(A), a lid member can be arranged so that the second slit is at least one slit zone 50 wherein a pair of discontinuous slits, inclined mutually outwardly, make a row along the boundary line and between the easily-peelable area A and the non-peelable area B.
Thus, when the second slit is the slit zone 50, since the second tab 3 breaks the slit zone 50 going through the adjacent slits successively, the surface sheet 40 in the easily-peelable area A can easily be separated, and the discharge apertures can also be opened more smoothly.
According to the another embodiment of the present invention, with reference to FIG. 5, a notch 18 is formed around the second tab 3 and is formed from the circumferential edge of the lid member to the second slit 5 (the slit zone 50) or to around the second slit 5.
Thereby, by pulling up the second tab 3, after the notch 18, the third slit 6 and the second slit 5 (the slit zone 50) are broken, in this order, and the surface sheet 40 in the easily-peelable area A is peeled from the base layer 20.
In particular, when the notch 18 is formed from the circumference edge of the lid member to the cross position e (See FIG. 3) by the second slit 5 and the third slit 6, peeling of the easily-peelable area A with the second tab 3 would be remarkably easy.